13.3. Model Behavior
275
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-
Hap standing stock
-Total fished biomass
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FIGURE 13.9
We then ran the model another one hundred times using the same settings, but including a 20% seeded random variance. The random variance
seems to damp the aforementioned relationship between Nile perch and
haplochromines, but it does not eliminate it (Figure 13.10).
In addition, intermediate fishing effort produces the greatest yield of marketable perch (Figure 13.11). Lower fishing effort allows the oldest and
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S 3.50E+13
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en
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5.00E+12
Effort
FIGURE 13.10